Bluetooth™ and Wi-Fi™ are two commonly used wireless data transmission protocols. Wi-Fi and Bluetooth both occupy a section of the 2.4 GHz Industrial, Scientific, and Medical (“ISM”) band that is 83 MHz-wide. Bluetooth is an industrial specification that can be used for wireless personal area networks (“PANs”). Bluetooth can be used to connect and exchange information between devices such as mobile phones, laptops, personal computers, hand-held computers, printers, digital cameras, and video game consoles. Bluetooth can be particularly useful when transferring information between two or more devices that are near each other in low-bandwidth situations. Common applications of Bluetooth can include wireless control of and communication between a mobile phone and a hands-free headset (e.g., a Bluetooth earbud), wireless networking between computers for certain applications, and wireless communications between a computer and input and output devices (e.g., mice, keyboards, and printers). Bluetooth uses Frequency Hopping Spread Spectrum (“FHSS”) and is allowed to hop between 79 different 1 MHz-wide channels in the ISM band.
Wi-Fi, an abbreviation of “wireless fidelity,” refers to wireless technology based upon the IEEE 802.11 standards generally used for local area networking. Common applications for Wi-Fi include internet access and network connectivity for consumer electronics such as televisions, DVD players, and digital cameras. Wi-Fi generally uses the same radio frequencies as Bluetooth, but operates using higher power, generally resulting in a stronger connection that can cover a greater distance. Wi-Fi uses Direct Sequence Spread Spectrum (DSSS) instead of FHSS. Its carrier does not hop or change frequency, and is instead maintained on one channel that is 22 MHz-wide. There is room for 11 overlapping Wi-Fi channels in the ISM band, but there is only room for three non-overlapping channels. This means that no more than three different Wi-Fi networks may operate in close proximity to one another.
Because both Wi-Fi and Bluetooth wireless technology share spectrum and can often be located in close physical proximity to one another, there is a likelihood that some interference will occur. Neither Wi-Fi nor Bluetooth was originally designed with mechanisms in place to deal with the interference that each creates for the other. While Wi-Fi and Bluetooth technology can continue to function during interference, increasing levels of interference can result in a slowing of the data rate as more packets need to be resent. In some conditions of extreme interference, communications can cease altogether.
Interference can particularly be a concern in electronic devices that contain both Wi-Fi and Bluetooth technology, such as smart wireless telephones and other similar devices. While such devices may operate if the problem is ignored, data rate degradation may occur as described above. This degradation can affect the user, for example, in the form of degradation of audio quality heard in a Bluetooth earbud. Another potential problem occurs when the Bluetooth receiver contained within the device is saturated by Wi-Fi transmissions, or vice versa.